The invention relates to a light construction plug for coke oven doors of horizontal chamber coking ovens, consisting of box-like, heat-resistant metallic hollow bodies which are fastened to the door body and can be filled with insulating material of low specific gravity.
In recent times there has been a demand on the part of technology for light coke oven doors. Because of extreme height of the modern coking ovens of up to 8 m, doors of conventional construction are very heavy, and consequently also the operating machines, as for example the coke oven door lifters, become heavier and heavier. An attempt has therefore been made to replace the conventional construction with a heavy plug of refractory brick materials by lighter models. At a reduced weight of the brick plug or door plug, also the construction of the door body itself or respectively of the door frame can be made lighter. It is a technological need to design the coke oven doors in such a way that their weight is substantially reduced.
Coke oven doors are known, for example, where the heavy brick plug is replaced by protective shields, usually of metallic materials. These heat protection shields are secured to the door body by means of spacers and form a vertical gas collection space which communicates with the horizontal gas collection space above the coal cake (German DE-OS No. 29 45 017). In this publication it has been proposed also to let the hollow plug extend less far into the chamber or respectively to reduce the distance between the door body and the heat protection shield in comparison with the thickness of the heavy refractory brick plugs, in order to increase the chamber volume of the coke oven and hence the coke production.
Also, the heavy brick plugs have been provided with vertical channels, so that in the vicinity of the oven door a gas-side pressure equalization between the lower and upper portions of the oven chamber could be established (U.S. Pat. No. 4,217,177). Then, however, there was the danger of these channels becoming clogged in time, because graphite depositions would form on the walls and the graphite coating would gradually grow until an insufficient passage of gas, or none at all, would occur.
German DE-OS No. 16 71 347 discloses the realization and design of a light door plug and a closure device for horizontal coking ovens consisting of a door body with a plug of refractory mineral substances and a covering of a smooth, porefree, highly heat-resistant radiating sheet as well as of a door frame and a seal at the door body and door frame. A door plug covering sheet fills the gap toward the chamber walls and extends the chamber floor. This sheet is bent, forms wings, and is held by struts. On both sides of the plug a vertical gas flue (discharge channel) is formed, which is to serve for gas pressure equalization.